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Why does PostgreSQL perform sequential scan on indexed column?
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If the SELECT returns more than approximately 5-10% of all rows in the table, a sequential scan is much faster than an index scan.
This is because an index scan requires several IO operations for each row (look up the row in the ...
Rails: How can I set default values in ActiveRecord?
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See Paul Russell's comment on this answer for more details
If you're only selecting a subset of columns for a model (ie; using select in a query like Person.select(:firstname, :lastname).all) you will get a MissingAttributeError if your init method accesses a column that hasn't been included in the...
How to bind an enum to a combobox control in WPF?
...sSource="{Binding Source={StaticResource dataFromEnum}}"
SelectedItem="{Binding Path=CurrentEffectStyle}" />
</Grid>
</Window>
Draw attention on the next code:
xmlns:System="clr-namespace:System;assembly=mscorlib"
xmlns:StyleAlias="clr-namespace:Motion.VideoEf...
How to get the groups of a user in Active Directory? (c#, asp.net)
...urrentForest().Domains.Cast<Domain>();
var allSearcher = allDomains.Select(domain =>
{
var searcher = new DirectorySearcher(new DirectoryEntry("LDAP://" + domain.Name));
// Apply some filter to focus on only some specfic objects
searcher.Filter = String.Format("(&(&(ob...
How to change the name of an iOS app?
...matically change all project-name-related entries and will allow you to de-select some of them, if you want.
Press 'RENAME' and Xcode will do the rest. In the meanwhile Xcode may ask you about the option of making a snapshot of the project (it is very recommendable to do so).
In addition to renami...
How to load json into my angular.js ng-model?
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<div ng-controller='MikesAngularController'>
<span>Please select a customer:</span>
<select ng-model="selectedCustomer" ng-options="customer.CustomerID as customer.CompanyName for customer in listOfCustomers" style="width:350px;"></select>
</div>
And th...
How to swap the buffers in 2 windows emacs
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If you just want to swap windows (independent on the selected one), you can use the following (defun win-swap () "Swap windows using buffer-move.el" (interactive) (if (null (windmove-find-other-window 'right)) (buf-move-left) (buf-move-right)))
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Disable XML validation in Eclipse
...ngs (disable the validation for this project): Right-click on the project, select Properties > Validation and uncheck the manual and build for: XML Schema Validator, XML Validator
Right-click on the project and select Validate to make the errors disappear.
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jQuery: checking if the value of a field is null (empty)
... be null, it's always a string value. this isn't entirely true. I've got a select containing no options. When I perform .val() on this it returns null. Jquery 1.7.2
– Liam
Jan 14 '13 at 11:07
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Can “list_display” in a Django ModelAdmin display attributes of ForeignKey fields?
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@marcelm that’s what select_related is for. the get_queryset() of the UserAdmin will have to be overwritten.
– interDist
Jul 17 '17 at 21:38
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